Not Applicable
This invention relates to a printhead chip for an ink jet printhead. More particularly, this invention relates to a printhead chip that includes a plurality of symmetrically actuated, moving nozzle arrangements.
The following applications are incorporated by reference:
As set out in the above referenced applications/patents, the Applicant has spent a substantial amount of time and effort in developing printheads that incorporate micro electromechanical system (MEMS)xe2x80x94based components to achieve the ejection of ink necessary for printing.
As a result of the Applicant""s research and development, the Applicant has been able to develop printheads having one or more printhead chips that together incorporate up to 84000 nozzle arrangements. The Applicant has also developed suitable processor technology that is capable of controlling operation of such printheads. In particular, the processor technology and the printheads are capable of cooperating to generate resolutions of 1600 dpi and higher in some cases. Examples of suitable processor technology are provided in the above referenced patent applications/patents.
The Applicant has overcome substantial difficulties in achieving the necessary ink flow and ink drop separation within the ink jet printheads.
As can be noted in the above referenced patents/patent applications, a number of printhead chips developed by the Applicant include a structure that defines an ink ejection port. The structure is displaceable with respect to the substrate to eject ink from a nozzle chamber. This is a result of the displacement of the structure reducing a volume of ink within the nozzle chamber. A particular difficulty with such a configuration is achieving a sufficient extent and speed of movement of the structure to achieve ink drop ejection. On the microscopic scale of the nozzle arrangements, this extent and speed of movement can be achieved to a large degree by ensuring that movement of the ink ejection structure is as efficient as possible.
The Applicant has conceived this invention to achieve such efficiency of movement.
According to the invention, there is provided a printhead chip for an ink jet printhead, the printhead chip comprising
a substrate; and
a plurality of nozzle arrangements that are positioned on the substrate, each nozzle arrangement comprising
an active ink ejection structure that is positioned on the substrate and spaced from the substrate, the active ink ejection structure having a roof with an ink ejection port defined in the roof;
a static ink ejection structure positioned on the substrate, the active ink ejection structure and the static ink ejection structure together defining a nozzle chamber in fluid communication with an ink supply, the active ink ejection structure being displaceable with respect to the static ink ejection structure towards and away from the substrate to reduce and increase a volume of the nozzle chamber to eject an ink drop from the nozzle chamber; and
at least two actuators that are operatively arranged with respect to the active ink ejection structure to displace the active ink ejection structure with respect to the static ink ejection structure towards and away from the substrate, the actuators being configured and connected to the active ink ejection structure to impart substantially rectilinear movement to the active ink ejection structure.
The invention is now described, by way of example, with reference to the accompanying drawings. The following description is not intended to limit the broad scope of the above summary.